From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0F778EF585B for ; Sun, 15 Feb 2026 03:58:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=ZCuFX4wLWSbnn2ULZdbzI2FlhLkmO20FWopmI/RY+50=; b=ixU1iUP7r2UEvBPdeEvgfNykrK hpH9VJSj1sUZKbTETHXIhrus9EuT9Q+oY7c7nLNbBmrf9ugEFDYi3q1QlOwpo3kJTybYTQLmXnbVt UIj+YUPw1/C/3xlC51dHP15Ycph/rwD/jM1fPJTfW6X+pbg/cXEKtyjKHjVt3c1lQ0waW28BQ4sO+ EuPsyQbCboDH9hrw7NT8XjSiwyVBbD+LXx96VKKXyLK5AzE1cX/nP8ZkcTY0tVsXCBXL0GeA9cPrm aoXuDOv4jBa3AtcL2aEWuolbAcgemRhudvs52EPhsaSDydbnEO9Du7tHrKN7+pabYvR2dhbU3Z9Im KdzZkb5w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vrTGy-000000058e2-3qM4; Sun, 15 Feb 2026 03:58:16 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vrTGx-000000058dv-1cTG for linux-arm-kernel@lists.infradead.org; Sun, 15 Feb 2026 03:58:15 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 8D5ED6001D; Sun, 15 Feb 2026 03:58:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 809A0C4CEF7; Sun, 15 Feb 2026 03:58:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771127892; bh=jsM6rUIEAwjwmIUoIADEtW5CiHC9ZcogfvHijHZpuys=; h=From:To:Cc:Subject:Date:From; b=AXEQZIueajJ7DSzROwzTv2ACIB0cWHnp8cKrN44oY7F4k5wUfahMoqA1vTzqNfbic RwRxyMU+tZqNsGzixcYy6Ki0Qfr23XH4NNGEbFTo5/8YzsXtaSCg3EyCjZYPvGq+nn 7HXhlPR3evjZ+YVDMQV+NrTqlGmIDV1D4j+kMXdIgp95bsUYdMg3Q3DWAMcTQKsZji zS04TsnIjwFpvY09XV8HoOOTzoZ5yFJ3X/3byZt7Ur66jeGGpy7QAsqqBb6hXRrXBw b8j+qnMVgtbnVUUoDY5Py9xed73WuybqloJ/+Mc/QaiAlzD5jqskm8p75qTOXUul0E mSLg6dyP46nLw== From: Jisheng Zhang To: Catalin Marinas , Will Deacon , Dennis Zhou , Tejun Heo , Christoph Lameter Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH] arm64: remove HAVE_CMPXCHG_LOCAL Date: Sun, 15 Feb 2026 11:39:44 +0800 Message-ID: <20260215033944.16374-1-jszhang@kernel.org> X-Mailer: git-send-email 2.51.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org It turns out the generic disable/enable irq this_cpu_cmpxchg implementation is faster than LL/SC or lse implementation. Remove HAVE_CMPXCHG_LOCAL for better performance on arm64. Tested on Quad 1.9GHZ CA55 platform: average mod_node_page_state() cost decreases from 167ns to 103ns the spawn (30 duration) benchmark in unixbench is improved from 147494 lps to 150561 lps, improved by 2.1% Tested on Quad 2.1GHZ CA73 platform: average mod_node_page_state() cost decreases from 113ns to 85ns the spawn (30 duration) benchmark in unixbench is improved from 209844 lps to 212581 lps, improved by 1.3% Signed-off-by: Jisheng Zhang --- arch/arm64/Kconfig | 1 - arch/arm64/include/asm/percpu.h | 24 ------------------------ 2 files changed, 25 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 38dba5f7e4d2..5e7e2e65d5a5 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -205,7 +205,6 @@ config ARM64 select HAVE_EBPF_JIT select HAVE_C_RECORDMCOUNT select HAVE_CMPXCHG_DOUBLE - select HAVE_CMPXCHG_LOCAL select HAVE_CONTEXT_TRACKING_USER select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_CONTIGUOUS diff --git a/arch/arm64/include/asm/percpu.h b/arch/arm64/include/asm/percpu.h index b57b2bb00967..70ffe566cb4b 100644 --- a/arch/arm64/include/asm/percpu.h +++ b/arch/arm64/include/asm/percpu.h @@ -232,30 +232,6 @@ PERCPU_RET_OP(add, add, ldadd) #define this_cpu_xchg_8(pcp, val) \ _pcp_protect_return(xchg_relaxed, pcp, val) -#define this_cpu_cmpxchg_1(pcp, o, n) \ - _pcp_protect_return(cmpxchg_relaxed, pcp, o, n) -#define this_cpu_cmpxchg_2(pcp, o, n) \ - _pcp_protect_return(cmpxchg_relaxed, pcp, o, n) -#define this_cpu_cmpxchg_4(pcp, o, n) \ - _pcp_protect_return(cmpxchg_relaxed, pcp, o, n) -#define this_cpu_cmpxchg_8(pcp, o, n) \ - _pcp_protect_return(cmpxchg_relaxed, pcp, o, n) - -#define this_cpu_cmpxchg64(pcp, o, n) this_cpu_cmpxchg_8(pcp, o, n) - -#define this_cpu_cmpxchg128(pcp, o, n) \ -({ \ - typedef typeof(pcp) pcp_op_T__; \ - u128 old__, new__, ret__; \ - pcp_op_T__ *ptr__; \ - old__ = o; \ - new__ = n; \ - preempt_disable_notrace(); \ - ptr__ = raw_cpu_ptr(&(pcp)); \ - ret__ = cmpxchg128_local((void *)ptr__, old__, new__); \ - preempt_enable_notrace(); \ - ret__; \ -}) #ifdef __KVM_NVHE_HYPERVISOR__ extern unsigned long __hyp_per_cpu_offset(unsigned int cpu); -- 2.51.0